Button in Android Studio

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Button in Android Studio

Buttons are one of the most important user interface elements in Android apps. Since a button is one of the most common controls in programming, it is the base class for the CompoundButton class and is inherited from TextView.

Button in Android Studio

by

Viktoriia Domukhovska

September 19, 2023

Buttons are one of the most important user interface elements in Android apps. Since a button is one of the most common controls in programming, it is the base class for the CompoundButton class and is inherited from TextView. The CompoundButton class in turn is the parent class for items such as CheckBox, ToggleButton, and RadioButton. Android uses the android.widget.Button class to create a button. The text is placed on the button, and you must click it to get the result. Instead of a button, you can use the ImageButton component (android.widget.ImageButton) where an image is applied instead of text.

In Android Studio, the button is represented as a Button component in the Widgets section. The font size, text color and other properties of the button can be configured using the textAppearance attribute, which applies system styles. 

Because the button inherits from TextView, it also uses many familiar attributes such as textColor, textSize and others. In the table below, you can see the main attributes that are used to create buttons:

Let’s find out how to create a button in Android Studio.

Changing the appearance of the button

In Android Studio, you can customize the appearance of the button using various properties. For example, you can change the background color, add an icon, or change the text of the button. Here are a few Android buttons examples:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
 xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:app="http://schemas.android.com/apk/res-auto"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:background="#168BC34A"
 tools:context=".MainActivity">
 <!-- Button added in the XML -->
 <Button
 android:id="@+id/button"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:background="#4CAF50"
 android:paddingStart="10dp"
 android:paddingEnd="10dp"
 android:text="@string/btn"
 android:textColor="@android:color/background_light"
 android:textSize="24sp"
 app:layout_constraintBottom_toBottomOf="parent"
 app:layout_constraintEnd_toEndOf="parent"
 app:layout_constraintStart_toStartOf="parent"
 app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

Working with different types of buttons

Android Studio offers a variety of buttons that prove valuable in various situations. Among the frequently encountered buttons are the following:

• ToggleButton (toggle): allows the user to toggle the state between on and off.
• ImageButton (image): displays an image instead of text on the button.
• FloatingActionButton: used for basic actions in an application and usually placed at the bottom of the screen.
• CheckBox: allows the user to toggle between two states: checked and unchecked.

Add the button’s functionality to the MainActivity. In this case, use an operation to display a popup message when the user clicks the button. Here you can see Android buttons example:

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Button
import android.widget.Toast
class MainActivity: AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle ? ) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val button = findViewById < Button > (R.id.button)
        // when the user tap on the button
        button.setOnClickListener {
            // displaying a toast message
            Toast.makeText(this @MainActivity, "Button was clicked", Toast.LENGTH_LONG).show()
        }
    }
}

In this case, we are looking for the button using the findViewById() method and setting the click handler using the setOnClickListener() method. Inside this handler, we pop up a toast using a Toast object to display information about the button being clicked.

We hope this Android Studio button tutorial helped you!